Novel EtG Based Contingency Management for Alcohol in the Severely Mentally Ill We propose to conduct a randomized clinical trial investigating the effect of a 12-week ethyl glucuronide (EtG) urinalysis based contingency management (CM) intervention on decreasing alcohol use and increasing alcohol treatment attendance among persons with alcohol dependence (AD) and serious mental illness (SMI) receiving long-term community mental health treatment. While CM is an evidence-based treatment for illicit drug use, research regarding its efficacy for AD has been limited due to the absence of a pragmatic alcohol biomarker to base the CM paradigm upon. This study will include the novel application of EtG urine-tests, capable of detecting alcohol use for a two-day period similar to urine-tests of illicit drug use, on which most CM drug research has been based. EtG results will be utilized as both a research outcome and as a basis on which the CM intervention targeting alcohol use is based. In addition, the CM paradigm will include secondary reinforcement of attendance in intensive outpatient (IOP) addiction treatment. It is hypothesized that this secondary contingency will result in higher rates of IOP attendance. 120 AD-SMI adults will participate in a 4-week induction period (reinforcement for providing urinalysis three times a week). All participants will receive treatment as usual (TAU) for SMI and intensive outpatient (IOP) addiction treatment throughout the study. After an induction period participants will be randomized to receive either 1) 12 weeks of CM for alcohol abstinence (assessed 3 times a week by EtG urine-tests) AND weekly reinforcement for IOP addiction treatment attendance; or 2) 12 weeks of reinforcement for providing urine-tests 3 times a week. The primary outcome will be changes in alcohol use assessed by EtG urinalysis, breathalyzer, as well as self-reported and clinician-reported alcohol use. The secondary outcome will be changes in IOP addiction treatment attendance assessed by IOP clinician-report, as well as independent administrative data sources, and self-report. Other outcomes will include: biological measures of illicit drug use, self-reported illicit drug use, psychiatric symptoms, HIV-risk, nicotine use, and utilization f costly emergency department, inpatient psychiatric and residential addiction treatment services. All outcomes will be assessed across the 12-week intervention and a 3-month follow-up period. This proposed study addresses two public health priorities--alcohol use and poor treatment attendance--in a population of adults with SMI for whom these difficulties are especially prevalent and problematic; and is responsive to NIAAA PA-10-100, Alcohol Use Disorders: Treatment, Services Research, and Recovery (R01).